Imagine you try hard making dinner and afterwords they put there hand on your shoulder and they said. "I love you sweetheart so I have to honest with you, your cooking has room for improvement. I don't want to hurt your feelings I just want to honest with you. But I believe you can learn to be great at cooking."
If they mentioned it in a kind way, like you described, and were not rude about it, I would actually appreciate their honest feedback. I would also probably ask them to help me out in becoming a better cook! :)
I'd laugh, because my cooking sucks, and you know what, they tried to say it sweetly, and not just insult you, so appreciate that. If they didn't like a meal, it doesn't have anything to do with them liking you, nor should it become an issue lol